Posts by LWN (old posts, page 13)

[$] LWN.net Weekly Edition for June 12, 2025

Inside this week's LWN.net Weekly Edition:

  • Front: Nyxt; Cyber Resilience Act; Unwanted file descriptors; Core-dump API; 6.16 Merge window; Uniprocessor configurations; Smatch; FUSE zero-copy; iov_iter; Fedora documentation.
  • Briefs: Android tracking; /e/OS 3.0; FreeBSD laptops; Ubuntu X11 support; Netdev 0x19; OIN anniversary; Quotes; ...
  • Announcements: Newsletters, conferences, security updates, patches, and more.

[$] Finding locking bugs with Smatch

Smatch is a GPL-licensed static-analysis tool for C that has a lot of specialized checks for the kernel. Smatch has been used in the kernel for more than 20 years; Dan Carpenter, its primary author, decided last year that some details of its plugin system were due for a rewrite. He spoke at Linaro Connect 2025 about his work on Smatch, the changes to its implementation, and how those changes enabled him to easily add additional checks for locking bugs in the kernel.

Covert web-to-app tracking via localhost on Android

The "Local Mess" GitHub repository is dedicated to the disclosure of an Android tracking exploit used by (at least) Meta and Yandex.

While there are subtle differences in the way Meta and Yandex bridge web and mobile contexts and identifiers, both of them essentially misuse the unvetted access to localhost sockets. The Android OS allows any installed app with the INTERNET permission to open a listening socket on the loopback interface (127.0.0.1). Browsers running on the same device also access this interface without user consent or platform mediation. This allows JavaScript embedded on web pages to communicate with native Android apps and share identifiers and browsing habits, bridging ephemeral web identifiers to long-lived mobile app IDs using standard Web APIs.

This backdoor, the use of which has evidently stopped since its disclosure, allow tracking of users across sites regardless of cookie policies or use of incognito browser modes.

Security updates for Wednesday

Security updates have been issued by AlmaLinux (glibc, grafana, kernel-rt, libjpeg-turbo, libxslt, and thunderbird), Debian (curl), Fedora (dtk6core, dtk6gui, dtk6log, dtk6widget, fcitx5-qt, gammaray, kddockwidgets, kwin, LabPlot, libqtxdg, nheko, plasma-integration, python-pyqt6, python-pyside6, qt-creator, roundcubemail, zeal, and a large number of qt6 packages), Oracle (firefox, glibc, grafana, kernel, libxslt, perl-FCGI, python3.12-cryptography, thunderbird, and zlib), SUSE (glib2, libjxl, libsoup2, nbdkit, nodejs22, perl-Crypt-OpenSSL-RSA, perl-YAML-LibYAML, python3, tomcat, and transfig), and Ubuntu (dotnet8, dotnet9 and samba).

Ubuntu 25.10 to drop support for GNOME on Xorg

Jean Baptiste Lallement, a member of Canonical's desktop team, has announced that Ubuntu will drop support for GNOME on X11 in the 25.10 ("Questing Quokka") release set for October. GNOME plans to remove X11 support in GNOME 49, which is scheduled for September, so Ubuntu is looking to be proactive:

Ubuntu 25.10 is the last interim release before our next LTS (Ubuntu 26.04). By moving now, we give developers and users a full cycle to adapt before the next LTS, align with GNOME 49 and reduce fragmentation while simplifying our support matrix heading into the LTS.

Fedora decided in early May to drop X11 support for GNOME in Fedora 43, which is also due in October.

[$] Improving iov_iter

The iov_iter interface is used to describe and iterate through buffers in the kernel. David Howells led a combined storage and filesystem session at the 2025 Linux Storage, Filesystem, Memory Management, and BPF Summit (LSFMM+BPF) to discuss ways to improve iov_iter. His topic proposal listed a few different ideas including replacing some iov_iter types and possibly allowing mixed types in chains of iov_iter entries; he would like to make the interface itself and the uses of iov_iter in the kernel better.

[$] Improving Fedora's documentation

At Flock, Fedora's annual developer conference, held in Prague from June 5 to June 8, two members of the Fedora documentation team, Petr Bokoč and Peter Boy, led a session on the state of Fedora documentation. The pair covered a brief history of the project's documentation since the days of Fedora Core 1, challenges the documentation team faces, as well as plans to improve Fedora's documentation by enticing more people to contribute.

Security updates for Monday

Security updates have been issued by AlmaLinux (golang, nodejs22, thunderbird, and varnish), Debian (gimp, modsecurity-apache, python-tornado, and roundcube), Fedora (chromium, coreutils, fcgi, ghostscript, krb5, libvpx, mingw-gstreamer1-plugins-bad-free, mingw-libsoup, mod_security, and samba), Mageia (php-adodb, systemd, and tomcat), Red Hat (buildah, firefox, glibc, grafana, kernel, libsoup, libxslt, mod_security, perl-FCGI, podman, python-tornado, and skopeo), Slackware (libvpx), and SUSE (helm-mirror, iputils, and libraw).